It is usually caused by viruses viz. Andenovirus, rhinovirus, influenza virus, parainfluenza and respiratory syncytial virus.

These are spread by droplet infection.

Predisposing, Factors

Pathogenesis

The viruses, first invade the surface ciliated andnon-ciliated epithelial cells resulting in congestion and shedding of the cilia followed by invasion of deeper epithelial cells. This leads to denudation of the mucosa and edema of subepithelial tissue resulting in congestion. Initially upper respiratory tract cells are affected but as disease progresses lower respiratory tract is also involved.

Clinical Features

Initially there is irritation and feeling ofnasal congestion - Sneezing - Nasal discharge initially watery and eventually becomes mucoid or purulent - fever and rigor Medical Management - No Antibiotics are given unless there is secondary bacterial infection - Synptomatic treatment is given with analagesics, decongestants, antihistamines et